<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      .box {
        width: 200px;
        height: 200px;
        border: 3px solid black;
        font-size: 30px;
        margin-top: 10px;
      }
      .pink {
        background-color: pink;
      }
      .big {
        width: 300px;
        height: 300px;
      }
    </style>
  </head>
  <body>
    <div id="app">
      {{msg}}
      <!-- 对象格式 -->
      <div class="box" :class="{ pink:true, big:true}">测试字体大小</div>  
      <!-- 数组 -->
      <div class="box" :class="['pink','big']"></div>
    </div>
  </body>

  <script src="js/vue.js"></script>
  <script>
    const app = new Vue({
      el: "#app",
      data: {
        msg: "hello world",
      },
      methods: {},
    });
  </script>
</html>
